diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index ac7d7757ec..eae0a372b5 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -20,6 +20,7 @@ Test fixtures for use by clients are available for each release on the [Github r
 - 🔀 Helper methods `to_address`, `to_hash` and `to_hash_bytes` have been deprecated in favor of `Address` and `Hash`, which are automatically detected as opcode parameters and pushed to the stack in the resulting bytecode ([#422](https://github.com/ethereum/execution-spec-tests/pull/422)).
 - ✨ `Opcodes` enum now contains docstrings with each opcode description, including parameters and return values, which show up in many development environments ([#424](https://github.com/ethereum/execution-spec-tests/pull/424)) @ThreeHrSleep.
 - 🔀 Locally calculate state root for the genesis blocks in the blockchain tests instead of calling t8n ([#450](https://github.com/ethereum/execution-spec-tests/pull/450)).
+- 🐞 Fix bug that causes an exception during test collection because the fork parameter contains `None` ([#452](https://github.com/ethereum/execution-spec-tests/pull/452)).
 
 ### 🔧 EVM Tools
 
diff --git a/src/pytest_plugins/test_filler/test_filler.py b/src/pytest_plugins/test_filler/test_filler.py
index a468d495c2..44cffb5faa 100644
--- a/src/pytest_plugins/test_filler/test_filler.py
+++ b/src/pytest_plugins/test_filler/test_filler.py
@@ -241,7 +241,7 @@ def do_fixture_verification(request, t8n) -> bool:
 @pytest.fixture(autouse=True, scope="session")
 def evm_fixture_verification(
     request, do_fixture_verification: bool, evm_bin: Path, verify_fixtures_bin: Path
-) -> Optional[Generator[TransitionTool, None, None]]:
+) -> Generator[Optional[TransitionTool], None, None]:
     """
     Returns the configured evm binary for executing statetest and blocktest
     commands used to verify generated JSON fixtures.
@@ -493,6 +493,9 @@ def pytest_collection_modifyitems(config, items):
     for item in items[:]:  # use a copy of the list, as we'll be modifying it
         if isinstance(item, EIPSpecTestItem):
             continue
+        if "fork" not in item.callspec.params or item.callspec.params["fork"] is None:
+            items.remove(item)
+            continue
         if item.callspec.params["fork"] < Paris:
             # Even though the `state_test` test spec does not produce a hive STATE_TEST, it does
             # produce a BLOCKCHAIN_TEST_HIVE, so we need to remove it here.